Sheet catching and stacking mechanism



O\N O O O \N 0 \w O 0 fiwm H. W. THEISS Filed Nov. 28, 1958 SHEET CATCHING AND STACKING MECHANISM Patented Dec. 19, 1939 UNITED STATES SI IEET CATCHING .AND STACKING- MECHANISM Harry W. Theiss, Louisville, Ohio, assignor to Continental Steel Corporation,',Kokomo, Ind,v a corporation of Indiana Application November 2a; 1938, Serial no. 242,750

' 12 Claims.

. a'nd the object of the present invention is to make provision for the linear advance of the sheets to the point of deposit and for their release atthis point so that they will fall uniformly in position in.the building up of a stack to the desired dimensions. r

In order to deposit the sheets from above, it

is necessary to provide mechanism which will not stack without the provision of any underlying support.

Further objects and details will appear from the description of the invention in conjunction with the accompanying-drawing, wherein,-

Figure 1 is a sectional view of the apparatus embodying the features of the present invention;

Fig. 2 is atop or .plan view thereof; and

Fig. 3 is a wiring diagram of the magnetic rolls and circuits for controlling them.

The metal sheets.X, in the embodiment of the invention here shown, are discharged "from a heating furnace Ill by the action of discharge '5 rolls II, but in view of the fact that the present invention nowise relates to any preliminary treatment of the sheets it is not deemed necessary to describe the furnace in detail. It will also be understood that the present mechanism-may be 0 associated with cleaning or pickling tanks, or-

other appliances or apparatus for treating or manipulating the sheets in any desired manner. The discharge rolls II are aligned with upper and lower spaced guide bars I2 formed of micarta,

which afford a guideway or channel forthe forward advance of the sheets to a permanently magnetized overhead roll l3 which constitutes the first of a series of aligned rolls, for advancing the sheets to the point of deposit. The remainder 5 of the series of rolls comprise the forwardgroup consisting of the rolls l4 and I5, and the reargroup consisting of the rolls l6, l1,- l8 and l9.

These two groups of rolls are wired, as later will be disclosed, for temporary magnetization, so that may be demagnetized at the proper intervals to effect deposit of the sheets on the stack 20.

In order to adequately guide the sheets under v the series of rolls, intervening overhead guide bars 2| of micarta are provided between each of 5 the magnetizable rolls and in alignment with the upper guide bars 12, gaps being afforded between the guide bars for the exposure of the under surfaces of the magnetizedand magnetizable rolls to a-slight.degree, so that positive contact with the magnetized surfaces may be effected. The guide bars, however, serve as strippers to prevent undue adhesion of the sheets upon the magnetic surfaces and to insure an even forward advance of the sheets while suspended from above. It will be noted that the ends of the guide bars adjacent the. surfaces of the rolls are beveled so that no' appreciable gaps are presented.

' Intermediate the rolls I1 and V I8 is a limit switch 22 provided with a pivoted roller 23 which is elevated by and rides upon the surface of an advancing sheet, and is pivoted to drop to a lower position when the trailing edge of the sheet passes the roller.

Each of the rolls l3 to l9 inclusive contains a magnet coil as l3, I4, 15,, I6, etc. Coil I3 is connected across thepower line 30. Coils Il and I5 are connected at one end through leads 3| and 32 to one side of the electric power line and at the other end through a lead 33 to one side of the switch 22, the opposite side of this switch being connected to the other side of the power line. Likewise, the magnet coils I6 l1, Ill and I9 are connected at one side in parallel through a lead 34 to one side of the power line and at the other side through a lead 35 to one side of the switch 24, the other side of the switch being connected to the opposite side of the power line.

Thus, as the leading edge of a sheet advances, 40 it liftsthe roller 23 thereby opening the switch I 22 which is normally closed by the weight of the roller. This demagnetizes the coils H I 5 and permits the trailing end of the sheet to ,drop away from the rolls I4, l5 as shown in Fig. 2 while it is still held by the later rolls l6, l1, l8, l9. The instant the sheet lifts the roller 25, the switch 24 opens thereby demagnetizing the remaining rolls causing the sheet to be dropped onthe stack 20. The rollers 23 and 25 then serve to again close the switches'22 and 24.

In order to properly align the sheets as they are deposited, a barrier plate 26 is provided, against which the forward edges of the sheets will abut as they are deposited by the rolls. The rolls are 5 all driven at a uniform feeding speed through the provision of suitable sprocket driving mechanism 21 actuated from a common source ofpower 28,

which mechanism, however, need not be described in detail.

Operation In use, the sheets delivered singly by the discharge rolls II, or in any other suitable man-- ner, are advanced through the guideway afforded by the bars l2 to the permanently magnetized roll I3, and as soon as contact is effected with this roll the forward edge of the sheet will be held elevated without underlying support. The roll l3 continues the advancement successively to the rolls l4, l5, I6 and I1, and as soon as the sheet advances beyond the roll l'l it will engage the roller 23 of'the limit switch 22 and lift the same slightly, which movement is availed of to actuate the limit switch and demagnetize the first group consisting of the rolls I4 and I5. This allows the trailing edge of the sheet to sag downwardly to someextent, as indicated, to aflord an easy clearance for the following sheet. this stage the advancement of the sheet is con tinued by the rolls l6 and I1, and thereafter also by. the rolls l8 and I9, so that at this stage the sheet will have magnetic contact with all four rolls in the second group, but as soon as the forward edge of the sheet engages and lifts the roller 25 of the limit switch 24, this will actuate the limit switch and demagnetize the four rolls constituting the second group, which permits the sheet to drop freely to the top of the stack, although at this stage there will be sufilcient forward momentum to cause the sheet to slide sufficiently to contact the barrier plate 26 which aligns all of the sheets in uniform vertical relation and serves to maintain the stack evenly during the accumulation ofthe sheets.

The apparatus as a whole is so constructed that the sheets at all times during the advancement will be held in magnetic contact ,with at least two rolls, so that an adequate grip will be afforded to advance the sheets evenly and certainly without sidewise slewing or deflection; and by the movement of the limit switches, and by actuating the rolls constantly at a predetermined feeding speed, provision is made for the uniform deposit of the sheets with due allowance for the forward thrust of the sheets after final release from the magnetic rollers and due to the momentum previously acquired.

Although the invention has been described with particularity as to detail, it is not the in-,

tention, unless otherwise indicated in the claims, to limit the invention to the-specific form shown, since modifications may be introduced without departing from the spirit of the invention.

;I claim:

1. In sheet stacking mechanism of the class described, the combination of a plurality of magnetizable rolls arranged in overhanging relation to the sheet feeding plane and adapted in sequence to magnetically engage,suspend and advance the sheets to the point of deposit, automatic means located at an intermediate point and actuated by the arrival of a sheet at said point for demagnetizing certain of the magnetizable rolls while leaving other rolls magnetized, and automatic means located adjacent the point of final deposit and actuated by the arrival of a sheet at that point for demagnetizing the remaining rolls to eifect'release and deposit of the sheets.

2. In sheet stacking mechanisms of the class described, the combination of a plurality of magnetizable rolls arranged in overhanging relation to the sheet feeding plane and adapted in sequence to magnetically engage, suspend and advance the sheets to the point of deposit, automatic means actuated by the arrival of a sheet for demagnetizing certain of the rolls to effect release and deposit of the sheet, and a stop barrier located adjacent the point of deposit for arresting the advance of the sheets after release by the magnetizable roll in efiecting an even stacking of the sheets.

3. In sheet stacking mechanism of the class described, the combination of a plurality of magnetizable rolls arranged in overhanging relation to the sheet feeding plane and adaptedin sequence to magnetically engage, suspend and advance the sheets to the point of deposit, automatic means located at an intermediate point and actuated by the arrival of a sheet at said point for demagnetizing certain of the magnetizable rolls while leaving other rolls magnetized, automatic means located adjacent the point of final deposit for demagnetizing the remaining rolls to effect release and deposit of the sheets, and a stop barrier located adjacent the point of deposit for arresting the advance of the sheets after release by the magnetizable roll in effecting an even stacking of the sheets.

4. In sheet stacking mechanism of the class described, the combination of a sheet supporting and advancing means, a series of magnetizable rolls having their lower feeding surfaces in aligned relation, means for rotating the rolls uniformly to advance the sheets in processional relation, means actuated by the arrival of a sheet at a predetermined position beyond the sheet supporting and advancing means for demagnetizing the magnetizable rolls and effecting deposit of the sheets, and a fixed barrier for arresting the forward advance of the sheets after release in effecting an even stacking of the sheets.

5. In sheet stacking mechanism of the class described, the combination of a sheet supporting and advancing means, a series of magnetizable rolls having their lower feeding surfaces in aligned relation, means for rotating-the rolls uniformly to advance the sheets in processional relation, means actuated by the arrival of a sheet at a predetermined position beyond the sheet supporting and advancing means for demagnetizing the magnetizable rolls and effecting deposit of the sheets, and aligned guide means interposed between the rolls in position to expose the lower surfaces of the rolls and direct the sheetsforward in an even line of advance.

6. In sheet stacking mechanism of the class described, the combination of a sheet supporting and advancing means, a series of magnetizable rolls having their lower feeding surfaces in aligned relation, means for rotating the rolls uniformly to advance the sheets in processional relation, .means actuated by the arrival of a sheet at a predetermined position beyond the sheet supporting and advancing means fordemagnetizing the magnetizable rolls and efiecting 7. In sheet stacking mechanism of the class H described, the combination of a magnetic sheet supporting and advancing means located in the advanced feeding position, a series of magnetizgroup'and actuated by the arrival of theleading edge of a sheet at that point to demagnetize the rolls of the second group to effect release and deposit of the sheet.

8. In sheet stacking mechanism of the class described, the combination of a magnetic sheet supporting and advancing means located in the advanced feeding position, a series of magnetliable rolls located progressively beyond the sheet supporting means and comprising two groups consisting each of a plurality 'of magnetizable rolls, automatic switch means actuated by the arrival of a sheet at a point beyond the first roll of the second group for demagnetizing the rolls of the first group to release the trailing end 'of a sheet while the leading end is in contact with a portion of the second group, automatic means located beyond the last roll of the second group and actuated'by the arrival of the leading edge of a sheet at that'point to demagnetize the rolls of the second group to efie'ct release and deposit of the sheets, and a fixed barrier for arresting the forward advance of the sheets after release in effecting an even stacking of the sheets.

.9. In sheet stacking mechanism of the class described, the combination of a plurality of spaced magnetic means arranged in a desired line of advance for suspending a ferrous sheet, means for advancing the sheet, means for demagnetizing certain of the magnet means as the sheet advances to release the trailing end of the sheet while the leading end is held by other magnetic means, and means for demagnetizing said other magnetic means to efiect release of the sheet and stacking thereof at a desired point of advance.

10. In sheet stacking mechanism of the class described, the combination of a plurality of spaced magnetic means arranged in a desired line of advance for suspending a'ferrous sheet,

-means for advancing the sheet, means operable by the sheet for demagnetizing certain of the magnet means as the sheet advances to release the trailing end of th sheet while the leading end is'held by other magnetic means, and means operable by thesheet for demagnetizing said other magnetic means to effect release of the sheet and stacking thereof at a desired point of advance.

11. The method of handling "and stacking ferrous sheets comprising moving one'sheet at a time beneath the first of a series of parallel rolls,

' magnetizing these rolls in advance of the leading edge of the sheet to support the sheet as it advances, progressively demagnetizing-the rolls as the sheet advances so as to release the trailing end of the sheet whilethe leading end is supported, and demagnetizing the remainingrolls to release the sheet entirely when it has advanced to a predetermined point. r

12. The method of handling and stacking ferrous sheets comprising advancing the sheets while held suspended at spaced progressive points in. the line of advance by magnetic flux, progressively stopping the magnetic-flux at'certain points as the sheet advances to drop the trailing edge of the sheet while the leading edge is heldsuspended, and stopping all magnetic flux when the sheet has advanced to a predetermined point to effect complete release and deposit of the sheet.

HARRY W. THEISS. 

